Today pilots have to obtain required information from a number of different sources like airport/SID/STAR/approach or
enroute charts (respectively their electronic representations), printouts like the flight plan or a weather briefing, and
updates via voice communications. The flight crew is required to mentally combine all this information. This situation
will become even more difficult to cope with in the SESAR/NextGen world with dynamic changes of the trajectory
(flight plan), and more frequent updates of weather, NOTAMs and other information requiring a higher degree of
automation and better information presentation.
To address these issues, lower the pilot's workload, and increase his situational awareness, a concept is presented where
all required information is provided through one application. Depending on the phase of flight (taxi-in/taxi-out,
departure, enroute, arrival, approach) the application will select the currently required information and provide a
seamless representation for the crew. The challenge is to provide the right information at the right time to the crew (e.g.
significant weather moving into the direction of the flight plan).
The focus of this paper will be on the components of the new application related to ground operations. This includes an
enhanced, AMM-like view with integrated taxi-routing support, graphical and textual display of chart notes (e.g.
wingspan restrictions, taxiway closures etc.), and updates of such information by automatic inclusion of digital
Input, management, and display of taxi routes on airport moving map displays (AMM) have been covered in various
studies in the past. The demonstrated applications are typically based on Aerodrome Mapping Databases (AMDB). Taxi
routing functions require specific enhancements, typically in the form of a graph network with nodes and edges modeling
all connectivities within an airport, which are not supported by the current AMDB standards. Therefore, the data
schemas and data content have been defined specifically for the purpose and test scenarios of these studies.
A standardization of the data format for taxi routing information is a prerequisite for turning taxi routing functions into
production. The joint RTCA/EUROCAE special committee SC-217, responsible for updating and enhancing the AMDB
standards DO-272  and DO-291 , is currently in the process of studying different alternatives and defining
Requirements for taxi routing data are primarily driven by depiction concepts for assigned and cleared taxi routes, but
also by database size and the economic feasibility. Studied concepts are similar to the ones described in the GDF
(geographic data files) specification , which is used in most car navigation systems today. They include
- A highly aggregated graph network of complex features
- A modestly aggregated graph network of simple features
- A non-explicit topology of plain AMDB taxi guidance line elements
This paper introduces the different concepts and their advantages and disadvantages.
Helicopter Emergency Medical Service missions (HEMS) impose a high workload on pilots due to short preparation
time, operations in low level flight, and landings in unknown areas. The research project PILAS, a cooperation between
Eurocopter, Diehl Avionics, DLR, EADS, Euro Telematik, ESG, Jeppesen, the Universities of Darmstadt and Munich,
and funded by the German government, approached this problem by researching a pilot assistance system which supports
the pilots during all phases of flight.
The databases required for the specified helicopter missions include different types of topological and cultural data for
graphical display on the SVS system, AMDB data for operations at airports and helipads, and navigation data for IFR
segments. The most critical databases for the PILAS system however are highly accurate terrain and obstacle data. While
RTCA DO-276 specifies high accuracies and integrities only for the areas around airports, HEMS helicopters typically
operate outside of these controlled areas and thus require highly reliable terrain and obstacle data for their designated
response areas. This data has been generated by a LIDAR scan of the specified test region. Obstacles have been extracted
into a vector format.
This paper includes a short overview of the complete PILAS system and then focus on the generation of the required
high quality databases.
An Obstacle, in the aviation context, may be any natural, man-made, fixed or movable object, permanent or temporary.
Currently, the most common way to detect relevant aviation obstacles from an aircraft or helicopter for navigation
purposes and collision avoidance is the use of merged infrared and synthetic information of obstacle data. Several
algorithms have been established to utilize synthetic and infrared images to generate obstacle information. There might
be a situation however where the system is error-prone and may not be able to consistently determine the current
environment. This situation can be avoided when the system knows the true position of the obstacle. The quality
characteristics of the obstacle data strongly depends on the quality of the source data such as maps and official
publications. In some countries such as newly industrializing and developing countries, quality and quantity of obstacle
information is not available. The aviation world has two specifications - RTCA DO-276A and ICAO ANNEX 15 Ch. 10
- which describe the requirements for aviation obstacles. It is essential to meet these requirements to be compliant with
the specifications and to support systems based on these specifications, e.g. 3D obstacle warning systems where accurate
coordinates based on WGS-84 is a necessity.
Existing aerial and satellite or soon to exist high quality remote sensing data makes it feasible to think about automated
aviation obstacle data origination. This paper will describe the feasibility to auto-extract aviation obstacles from remote
sensing data considering limitations of image and extraction technologies. Quality parameters and possible resolution of
auto-extracted obstacle data will be discussed and presented.
A new, open specification for embedded interchange formats for Airport Mapping Databases has been established in the
ARINC 816 document. The new specification has been evaluated in a prototypical implementation of ground and
airborne components. A number of advantages and disadvantages compared to existing solutions have been identified
and are outlined in this paper. A focus will be on new data elements used for automatic label placement on airport maps.
Possible future extensions are described as well.
An Airport Qualification may be required for a pilot to receive qualification for the execution of an approach or departure from a terrain, weather, or procedure challenging airport. The FAA identified these challenging airports and calls them "Special Pilot Qualification Airports". This Qualification may be accomplished through a familiarization using airport images or through a familiarization flight with an authorized person. Currently, Jeppesen offers Airport Familiarization Charts. These charts depict approach procedure photos to a runway from the pilot's perspective and aerial views of the airport. Before the approach, Pilots make use of these photos to get familiarized with the airport, the runway layout, the approach and terrain. Jeppesen qualification charts cover all FAA identified airports and other challenging airports. A first prototype for generating "Synthetic Airport Familiarization" pictures and videos has been researched, developed, implemented and validated. Flight Information Data as well as Remote Sensing Data and their derived data was processed and visualized through Geo Information System (GIS). This paper describes a new possibility to generate airport familiarization images using Remote Sensing Data, terrain data, airport vector data, obstacles and approach procedure data through GIS. The objective is to replace analogues photos with synthetic pictures and also to generate new Airport Familiarization Videos. Finally, an overview of the potential feature extensibility of the Synthetic Airport Familiarization System is presented.
Synthetic vision systems (SVS) are studied for some time to improve pilot's situational awareness and lower their
workload. Early systems just displayed a virtual outside view of terrain, obstacles or airport elements as it could also be
perceived through the cockpit windows in absence of haze, fog or any other factors impairing visibility. Required digital
terrain, obstacle and airport databases have been developed and standardized by Jeppesen as part of the NASA Aviation
Newer SVS displays also introduced different kinds of flight guidance symbology to help pilots to improve the overall
flight precision. The method studied in this paper is to display navigation procedures in the form of guidance channels.
First releases of the described system used static channels, generated once at the startup at the system or even offline.
While this approach is very resource friendly for the avionics hardware, it does not consider the users, which want the
system to respond to the current flight conditions dynamically.
Therefore, a new application has been developed which generates both the general channel trajectory as well as the
channel depiction in a fully dynamic way while the pilot flies a navigation procedure.
Helicopters are widely used for operations close to terrain such as rescue missions; therefore all-weather capabilities are
highly desired. To minimize or even avoid the risk of collision with terrain and obstacles, Synthetic Vision Systems
(SVS) could be used to increase situational awareness. In order to demonstrate this, helicopter flights have been
performed in the area of Zurich, Switzerland
A major component of an SVS is the three-dimensional (3D) depiction of terrain data, usually presented on the primary
flight display (PFD). The degree of usability in low level flight applications is a function of the terrain data quality.
Today's most precise, large scale terrain data are derived from airborne laser scanning technologies such as LIDAR
(light detection and ranging). A LIDAR dataset provided by Swissphoto AG, Zurich with a resolution of 1m was used.
The depiction of high resolution terrain data consisting of 1 million elevation posts per square kilometer on a laptop in
an appropriate area around the helicopter is challenging. To facilitate the depiction of the high resolution terrain data, it
was triangulated applying a 1.5m error margin making it possible to depict an area of 5x5 square kilometer around the
To position the camera correctly in the virtual scene the SVS had to be supplied with accurate navigation data. Highly
flexible and portable measurement equipment which easily could be used in most aircrafts was designed.
Demonstration flights were successfully executed in September, October 2005 in the Swiss Alps departing from Zurich.
In the future, modern airliners will use enhanced-synthesic vision systems (ESVS) to improve aeronautical
operations in bad weather conditions. Before ESVS are effectively found aboard airliners, one must develop a
multisensor flight simulator capable of synthetizing, in real time, images corresponding to a variety of imaging
modalities. We present a real-time simulator called ARIS (Airborne Radar and Infrared Simulator) which is
capable of generating two such imaging modalities: a forward-looking infrared (FLIR) and a millimeter-wave
radar (MMWR) imaging system. The proposed simulator is modular sothat additional imaging modalities can
be added. Example of images generated by the simulator are shown.
In the past Jeppesen has built and distributed worldwide terrain models for several Terrain Awareness and Warning
Systems (TAWS) avionics clients. The basis for this model is a 30 arc-second NOAA Globe dataset with higher
resolution data used where available (primarily in the US). On a large scale however these terrain models have a 900m
(3000ft) resolution with errors that can often add up to 650m (1800ft) vertically. This limits the use of these databases to
current TAWS systems and is deemed unusable for other aviation applications like SVS displays that require a more
resolute and accurate terrain model.
To overcome this deficiency, the target of this project was to develop a new worldwide terrain database providing a
consistent terrain model that can be used by current (TAWS) and future applications (e.g. 2D moving maps, vertical
situation displays, SVS).
The basis for this project is the recently released SRTM data from NGA that provides a more resolute, accurate and
consistent worldwide terrain model. The dataset however has holes in the peak and valley regions, desert, and very flat
areas due to irrecoverable data capture issues. These voids have been filled using new topography algorithms developed
in this project.
The error distribution of this dataset has been analyzed in relation to topography, acquisition method and other factors.
Based on this analysis, it is now possible to raise the terrain a certain amount, such that it can be guaranteed that only a
certain number of real terrain points are higher than the data stored in the terrain database. Using this method, databases
for designated confidence levels of 10-3, 10-5 and 10-8 - called TerrainScape level 1 - 3 - have been generated.
The final result of the project is a worldwide terrain database with quality factors sufficient for use in a broader range of
civil aviation applications.
This paper describes flight trials performed in Centennial, CO using a Piper Cheyenne owned and operated by Marinvent. The goal of the flight trial was to evaluate the objective performance of pilots using conventional paper charts or a 3D SVS display. Six pilots flew thirty-six approaches to the Colorado Springs airport to accomplish this goal. As dependent variables, positional accuracy and situational awareness probe (SAP) statistics were measured while analysis was conducted by an ANOVA test. In parallel, all pilots answered subjective Cooper-Harper, NASA TLX, situation awareness rating technique (SART), Display Readability Rating, Display Flyability Rating and debriefing questionnaires. Three different settings (paper chart, electronic navigation chart, 3D SVS display) were evaluated in a totally randomized manner. This paper describes the comparison between the conventional paper chart and the 3D SVS display. The 3D SVS primary flight display provides a depiction of primary flight data as well as a 3D depiction of airports, terrain and obstacles. In addition, a 3D dynamic channel visualizing the selected approach procedure can be displayed.
The result shows that pilots flying the 3D SVS display perform no worse than pilots with the conventional paper chart. Flight technical error and workload are lower, situational awareness is equivalent with conventional paper charts.
The paper describes flight trials performed in Centennial, CO with a Piper Cheyenne from Marinvent. Six pilots flew the Cheyenne in twelve enroute segments between Denver Centennial and Colorado Springs. Two different settings (paper chart, enroute moving map) were evaluated with randomized settings. The flight trial goal was to evaluate the objective performance of pilots compared among the different settings. As dependent variables, positional accuracy and situational awareness probe (SAP) were measured. Analysis was conducted by an ANOVA test. In parallel, all pilots answered subjective Cooper-Harper, NASA TLX, situation awareness rating technique (SART), Display Readability Rating and debriefing questionnaires.
The tested enroute moving map application has Jeppesen chart compliant symbologies for high-enroute and low-enroute. It has a briefing mode were all information found on today’s enroute paper chart together with a loaded flight plan are displayed in a north-up orientation. The execution mode displays a loaded flight plan routing together with only pertinent flight route relevant information in either a track up or north up orientation. Depiction of an own ship symbol is possible in both modes. All text and symbols are deconflicted. Additional information can be obtained by clicking on symbols. Terrain and obstacle data can be displayed for enhanced situation awareness.
The result shows that pilots flying the 2D enroute moving map display perform no worse than pilots with conventional systems. Flight technical error and workload are equivalent or lower, situational awareness is higher than on conventional paper charts.
We describe a multisensor (or multimodal)
flight simulator (FS), which is currently capable of generating forwardlooking
infrared (FLIR) imagery and is designed in such a way that modules can easily be added to produce
other types of imagery such as for millimeter-wave radar (MMWR). Such sensors are the basis for the enhanced
vision systems (EVS) that are currently considered for installation aboard commercial and military aircraft to
enhance the safety of operation in poor-visibility weather or even in zero-visibility weather. The main source
of information for our simulator is an airport database, which is, in part, intended for driving synthetic vision
systems (SVS). We describe the architecture of the simulator and of its FLIR module. Preliminary simulation
examples are also shown.
Future cockpit and aviation applications require high quality airport databases. Accuracy, resolution, integrity, completeness, traceability, and timeliness  are key requirements. For most aviation applications, attributed vector databases are needed. The geometry is based on points, lines, and closed polygons. To document the needs for aviation industry RTCA and EUROCAE developed in a joint committee, the DO-272/ED-99 document. It states industry needs for data features, attributes, coding, and capture rules for Airport Mapping Databases (AMDB).
This paper describes the technical approach Jeppesen has taken to generate a world-wide set of three-hundred AMDB airports. All AMDB airports are DO-200A/ED-76  and DO-272/ED-99  compliant. Jeppesen airports have a 5m (CE90) accuracy and an 10-3 integrity. World-wide all AMDB data is delivered in WGS84 coordinates. Jeppesen continually updates the databases.
The paper describes flight trials performed in Reno, NV. Flight trial were conducted with a Cheyenne 1 from Marinvent. Twelve pilots flew the Cheyenne in seventy-two approaches to the Reno airfield. All pilots flew completely andomized settings. Three different settings (standard displays, 2D moving map, and 2D/3D moving map) were evaluated. They included seamless evaluation for STAR, approach, and taxi operations. The flight trial goal was to evaluate the objective performance of pilots compared among the different settings. As dependent variables, positional and time accuracy were measured. Analysis was conducted by an ANOVA test. In parallel, all pilots answered subjective Cooper-Harper, situation awareness rating technique (SART), situational awareness probe (SAP), and questionnaires.This article describes the human factor analysis from flight trials performed in Reno, NV. Flight trials were conducted with a Cheyenne 1 from Marinvent. Thirteen pilots flew the Cheyenne in seventy-two approaches to the Reno airfield. All pilots flew completely randomized settings. Three different display configurations: Elec. Flight Information System (EFIS), EFIS and 2D moving map, and 3D SVS Primary Flight Display (PFD) and 2D moving map were evaluated. They included normal/abnormal procedure evaluation for: Steep turns and reversals, Unusual attitude recovery, Radar vector guidance towards terrain, Non-precision approaches, En-route alternate for non-IFR rated pilots encountering IMC, and Taxiing on complex taxi-routes.
The flight trial goal was to evaluate the objective performance of pilots for the different display configurations. As dependent variables, positional and time data were measured. Analysis was performed by an ANOVA test. In parallel, all pilots answered subjective NASA Task Load Index, Cooper-Harper, Situation Awareness Rating Technique (SART), and questionnaires.
The result shows that pilots flying 2D/3D SVS perform no worse than pilots with conventional systems. In addition, 3D SVS flying pilots have significantly better terrain awareness, more stable 180° deg turns, and enhanced positional awareness while taxiing on the ground. Finally, even non-IFR rated pilots are able to fly non-precision approaches under IMC with a 3D SVS.
Next generation of cockpit display systems will display mass data. Mass data includes terrain, obstacle, and airport databases. Display formats will be two and eventually 3D. A prerequisite for the introduction of these new functions is the availability of certified graphics hardware. The paper describes functionality and required features of an aviation certified 2D/3D graphics board. This graphics board should be based on low-level and hi-level API calls. These graphic calls should be very similar to OpenGL. All software and the API must be aviation certified. As an example application, a 2D airport navigation function and a 3D terrain visualization is presented. The airport navigation format is based on highly precise airport database following EUROCAE ED-99/RTCA DO-272 specifications. Terrain resolution is based on EUROCAE ED-98/RTCA DO-276 requirements.
Many of today's and tomorrow's aviation applications demand accurate and reliable digital terrain elevation databases. Particularly, to enhance a pilot's situational awareness with future 3D synthetic vision systems, accurate, reliable, and hi-resolution terrain databases are required to offer a realistic and reliable terrain depiction. On the other hand, optimized or reduced terrain models are necessary to ensure real-time rendering and computing performance. In this paper a method for adaptive terrain meshing and depiction for SVS is presented. The initial dat set is decomposed by using wavelet transform. By examining the wavelet coefficients, an adaptive surface approximation for various level-of-detail is determined at runtime. Additionally, the dyadic scaling of the wavelet transform is used to build a hierarchical quad-tree representation for the terrain dat. This representation enhances fast interactive computations and real-time rendering methods. For the integrated airport navigation function an airport mapping database compliant to the new DO-272 standard is processed and integrated in the realized system. The used airport database contains precise airport vector geometries with additional object attributes as background information. In conjunction these data set can be used for various airport navigation functions like automatic taxi guidance. Booth, the multi-resolution terrain concept and airport navigation function are integrated into a high-level certifiable 2D/3D scene graph rendering system. It runs on an aviation certifiable embedded rendering graphics board. The optimized combination of multi- resolution terrain, scene graph, and graphics boards allows it to handle dynamically terrain models up to 1 arc second resolution. The system s and dat processing acknowledges certification rules based on DO-178B, DO-254, DO-200A, DO- 272, and DO-276.
Today's Jeppesen approach charts depict a plan view approach chart that includes approach procedure, terrain, obstacle, and airport information. The vertical profile of the procedure is replicated in a chart underneath. TO integrate plan view and vertical chart elements, a 3D display format was realized. It combines all geometric chart elements into a Synthetic Vision System. It depicts 3D tunnel in the sky, terrain, obstacles, and airport information. Color coding is identical to Jeppesen charts. Symbology is extruded from 2D chart symbology. This approach might be excellent for pilots acquainted to the conventional charts.
The requirements for a terrain and obstacle database for various applications in guidance and navigation for low level flight and landing will be derived. Applications include displays for flight guidance and situation awareness and algorithms for ground collision avoidance and terrain reference navigation. Different methods used for data acquisition and processing will be discussed with respect to these requirements. The properties of these methods will be demonstrated by generation and validation of an example database.
Many of today's and tomorrow's aviation applications demand accurate and reliable digital terrain elevation databases. Particularly future Vertical Cut Displays or 3D Synthetic Vision Systems (SVS) require accurate and hi-resolution data to offer a reliable terrain depiction. On the other hand, optimized or reduced terrain models are necessary to ensure real-time rendering and computing performance. In this paper a new method for adaptive terrain meshing and depiction for SVS is presented. The initial data set is decomposed by using a wavelet transform. By examining the wavelet coefficients, an adaptive surface approximation for various Level-of-Detail is determined. Additionally, the dyadic scaling of the wavelet transform is used to build a hierarchical quad-tree representation for the terrain data. This representation enhances fast interactive computations and real-time rendering methods. The proposed terrain representation is integrated into a standard navigation display. Due to the multi-resolution data organization, terrain depiction e.g. resolution is adaptive to a selected zooming level or flight phase. Moreover, the wavelet decomposition helps to define local regions of interest. A depicted terrain resolution has a finer grain nearby the current airplane position and gets coarser with increasing aircraft distance. In addition, flight critical regions can be depicted in a higher resolution.
Many of today's and tomorrow's real-time aviation applications are demanding for accurate and reliable databases. Common TAWS implementations such as EGPWS or integrated navigation systems such as Dasa's Integrated Navigation and Flight Guidance System16 depend essentially on terrain elevation databases. Regarding these applications, the resolution, accuracy, and precision of available data are of primary concern. On the other hand, 4D Synthetic Vision Systems (SVS) require performance optimized terrain models for a real-time visualization. The content of such databases need to be reduced and accessible in a real-time format. In 4D SVS, safety critical terrain databases are essential. Even higher accuracy is required for more demanding tasks such as low-level flights, precision approaches, or landings. In this paper a process is described to accomplish the contradictory demands of accuracy and visualization performance. The complexity of hi- resolution terrain models is reduced to enhance the rendering performance. Two different decimation approaches are explained and the resulting terrain databases is described. Each representation of the generated elevation shapes comprises a coarser quantity of input data. A statistical error analysis of resulting altitude errors is presented. The presented results represent both an offline verification with highly accurate databases and a comparison with altimeter data measured by airplane sensors during flight trials. To evaluate the different databases and to examine specific terrain resolutions, multiple flight trials were performed.
In future aircraft cockpits SVS will be used to display 3D physical and virtual information to pilots. A review of prototype and production Synthetic Vision Displays (SVD) from Euro Telematic, UPS Advanced Technologies, Universal Avionics, VDO-Luftfahrtgeratewerk, and NASA, are discussed. As data sources terrain, obstacle, navigation, and airport data is needed, Jeppesen-Sanderson, Inc. and Darmstadt Univ. of Technology currently develop certifiable methods for acquisition, validation, and processing methods for terrain, obstacle, and airport databases. The acquired data will be integrated into a High-Quality Database (HQ-DB). This database is the master repository. It contains all information relevant for all types of aviation applications. From the HQ-DB SVS relevant data is retried, converted, decimated, and adapted into a SVS Real-Time Onboard Database (RTO-DB). The process of data acquisition, verification, and data processing will be defined in a way that allows certication within DO-200a and new RTCA/EUROCAE standards for airport and terrain data. The open formats proposed will be established and evaluated for industrial usability. Finally, a NASA-industry cooperation to develop industrial SVS products under the umbrella of the NASA Aviation Safety Program (ASP) is introduced. A key element of the SVS NASA-ASP is the Jeppesen lead task to develop methods for world-wide database generation and certification. Jeppesen will build three airport databases that will be used in flight trials with NASA aircraft.
In future aircraft cockpit designs SVS (Synthetic Vision System) databases will be used to display 3D physical and virtual information to pilots. In contrast to pure warning systems (TAWS, MSAW, EGPWS) SVS serve to enhance pilot spatial awareness by 3-dimensional perspective views of the objects in the environment. Therefore all kind of aeronautical relevant data has to be integrated into the SVS-database: Navigation- data, terrain-data, obstacles and airport-Data. For the integration of all these data the concept of a GIS (Geographical Information System) based HQDB (High-Quality- Database) has been created at the TUD (Technical University Darmstadt). To enable database certification, quality- assessment procedures according to ICAO Annex 4, 11, 14 and 15 and RTCA DO-200A/EUROCAE ED76 were established in the concept. They can be differentiated in object-related quality- assessment-methods following the keywords accuracy, resolution, timeliness, traceability, assurance-level, completeness, format and GIS-related quality assessment methods with the keywords system-tolerances, logical consistence and visual quality assessment. An airport database is integrated in the concept as part of the High-Quality- Database. The contents of the HQDB are chosen so that they support both Flight-Guidance-SVS and other aeronautical applications like SMGCS (Surface Movement and Guidance Systems) and flight simulation as well. Most airport data are not available. Even though data for runways, threshold, taxilines and parking positions were to be generated by the end of 1997 (ICAO Annex 11 and 15) only a few countries fulfilled these requirements. For that reason methods of creating and certifying airport data have to be found. Remote sensing and digital photogrammetry serve as means to acquire large amounts of airport objects with high spatial resolution and accuracy in much shorter time than with classical surveying methods. Remotely sensed images can be acquired from satellite-platforms or aircraft-platforms. To achieve the highest horizontal accuracy requirements stated in ICAO Annex 14 for runway centerlines (0.50 meters), at the present moment only images acquired from aircraft based sensors can be used as source data. Still, ground reference by GCP (Ground Control-points) is obligatory. A DEM (Digital Elevation Model) can be created automatically in the photogrammetric process. It can be used as highly accurate elevation model for the airport area. The final verification of airport data is accomplished by independent surveyed runway- and taxiway- control-points. The concept of generation airport-data by means of remote sensing and photogrammetry was tested with the Stuttgart/Germany airport. The results proved that the final accuracy was within the accuracy specification defined by ICAO Annex 14.
2For some of today's simulations very expensive, heavy, and large equipment is needed. In order to reduce prototyping and training costs, immersive 'Virtual Cockpit Simulation' (VCS) becomes very attractive. Head Mounted Displays (HMD), datagloves, and cheap 'Seating Bucks' are used to generate an immersive stereoscopic virtual environment (VE) for designers, engineers, and trainees. The entire cockpit, displays, and a visual are modeled as 3D computer generated geometry with textured surfaces. HMD resolution, field of view (FOV), tracker lag, and missing force feedback are critical human machine interface (HMI) components in VCS. For VCS applications task performance and transfer of training into reality have to be evaluated. In this paper two test series evaluating the VCS HMI dependencies based on HMD resolution and FOV are described. FOV limitations are especially important for a two seater virtual cockpit. Cross viewing, observing overhead, glareshield, and pedestal are critical for flying. Test persons had to deal with different FOV settings varying from 30 degrees to 100 degrees. Their task was to find and count light arbitrary points located at different panels in a limited time. To evaluate cross viewing test persons also had to detect light points besides them while reading text in front of them. Based on the test results a recommendation for a necessary FOV was given. The most demanding component for HMD resolution are virtual flight guidance displays rendered in a virtual scene at correct size and location. They consist of small moving low contrast symbols. Under a hi-resolution (1280 X 1024) HMD test persons were asked to read-out letters, numbers, and symbols of different sizes, movement speeds, and contrasts. Some test persons also had to fulfill an additional task to reduce their attention. From the test results a minimal necessary symbol, letter, and numbersize was determined for hi-resolution (hires) HMDs.
For some of today's simulations very expensive, heavy and large equipment is needed. Examples are driving, shipping, and flight simulators with huge and expensive visual and motion systems. In order to reduce cost, immersive `Virtual Simulation' becomes very attractive. Head Mounted Displays or Computer Animated Virtual Environments, Datagloves, and cheap `Seating Bucks' are used to generate a stereoscopic virtual environment for a trainee. Such systems are already in use for caterpillar, submarine, and F15-fighter simulation. In our approach we partially simulate an Airbus A340 cockpit. All interaction devices such as side stick, pedals, thrust-levers, knobs, buttons, and dials are modeled as 3D geometry. All other parts and surfaces are formed by images (textures). Some devices are physically available such as sidesticks, pedals, and thrust-levers. All others are replaced by plastic panels to generate a forced feedback for the pilots. A simplified outside visual is available to generate immersive flight simulations. A virtual Primary Flight display, Navigation display, and a virtual stereoscopic Head Up Display are used in a first approach. These virtual displays show basic information necessary to perform a controlled flight and allow basic performance analysis with the system. All parts such as physical input devices, virtual input devices, flight mechanics, traffic, and rendering run in a distributed environment on different high end graphics work stations. The `Virtual Cockpit' can logically replace an also available conventional cockpit mockup in the flight simulation.
In today's civil flight training simulators only the cockpit and all its interaction devices exist as physical mockups. All other elements such as flight behavior, motion, sound, and the visual system are virtual. As an extension to this approach `Virtual Flight Simulation' tries to subsidize the cockpit mockup by a 3D computer generated image. The complete cockpit including the exterior view is displayed on a Head Mounted Display (HMD), a BOOM, or a Cave Animated Virtual Environment. In most applications a dataglove or virtual pointers are used as input devices. A basic problem of such a Virtual Cockpit simulation is missing force feedback. A pilot cannot touch and feel buttons, knobs, dials, etc. he tries to manipulate. As a result, it is very difficult to generate realistic inputs into VC systems. `Seating Bucks' are used in automotive industry to overcome the problem of missing force feedback. Only a seat, steering wheel, pedal, stick shift, and radio panel are physically available. All other geometry is virtual and therefore untouchable but visible in the output device. In extension to this concept a `Seating Buck' for commercial transport aircraft cockpits was developed. Pilot seat, side stick, pedals, thrust-levers, and flaps lever are physically available. All other panels are simulated by simple flat plastic panels. They are located at the same location as their real counterparts only lacking the real input devices. A pilot sees the entire photorealistic cockpit in a HMD as 3D geometry but can only touch the physical parts and plastic panels. In order to determine task performance with the developed Seating Buck, a test series was conducted. Users press buttons, adapt dials, and turn knobs. In a first test, a complete virtual environment was used. The second setting had a plastic panel replacing all input devices. Finally, as cross reference the participants had to repeat the test with a complete physical mockup of the input devices. All panels and physical devices can be easily relocated to simulate a different type of cockpit. Maximal 30 minutes are needed for a complete adaptation. So far, an Airbus A340 and a generic cockpit are supported.
In future aircraft cockpit designs SVS databases will be used to display 3D physical and virtual information to pilots. One of the key elements is reliable display of terrain elevation data in order to increase situation awareness. Displayed data and the outside world must match concerning position and altitude. Therefore, terrain elevation data with specified error values are required to guarantee reliability and integrity. The determination of the database error imposes two major steps. The first step applies to the generation of the primary database. Today several companies start to provide elevation models generated by different methods taken from independent sources. If not stated, the error of these databases has to be calculated and verified by the use of reference data and statistical methods. Some commonly used models (like DTED) were investigated, errors estimated, and compared. The second step is required for the preparation of data to be used in a SVS. For most of today's graphics machines the amount of data is too large to be drawn at an acceptable frame rate. Therefore, polygonal decimation is used to reduce the number of triangles to be rendered. Most algorithms used for decimation were developed for the visual quality of the decimated terrain. Their parameters do not allow to perform an error bounded decimation because they are based on criterion like 'face angle' or 'bounding box size.' However, it is necessary to know the absolute error introduced by the decimation for an SVS. An algorithm was developed to eliminate vertices only if the newly introduced error is smaller than a given threshold. In addition, this algorithm tries to preserve important features such as ridgelines. Knowing the maximal altitude error of a certain position and the error introduced by decimation, it is possible to generate a worst case elevation error for that point.
In synthetic vision systems (SVS) environmental data and mission critical information must be provided to pilots and system components. For systems with demanding visual graphics representations or enhanced ground proximity warning systems (EGPWS), databases offer data in high resolution with distinct features. Investigations show that pre- and in-flight services and systems such as Aeronautical Publications (AIP), flight planning, map creation, FMS, flight displays, or EGPWS are all based on dependent data from few sources. They are usually terrain, cultural, flight related, weather, or NOTAMS based. Our concept proposes a single relational high quality database (HQ-DB) for all of the above described applications. It allows to store worldwide information in an appropriate resolution with a verified quality. Obviously such a HQ-DB will not be carried in an aircraft. The amount of data is too enormous and geographical information system storage formats do not allow real-time extraction of data. Therefore, for every application a separate real-time on board database (RTO-DB) is derived from the HQ-DB. In the off-line RTO-DB creation process, data is converted in a real-time capable graphics data format formed by tiles with integrated level of detail and geometric representations of synthetic objects. During a mission, the database server integrates pilot inputs and changes via data link. Manual inputs changing the appearance of primary flight displays can also directly influence the RTO-DB. The resulting data is sent to the application using this data. In our system this database concept is used for generic flight guidance displays, for a simulator visual display system, and for a general algorithmic flight hazard warning system.
Today's aircraft equipment comprise several independent warning and hazard avoidance systems like GPWS, TCAS or weather radar. It is the pilot's task to monitor all these systems and take the appropriate action in case of an emerging hazardous situation. The developed method for detecting and avoiding flight hazards combines all potential external threats for an aircraft into a single system. It is based on an aircraft surrounding airspace model consisting of discrete volume elements. For each element of the volume the threat probability is derived or computed from sensor output, databases, or information provided via datalink. The position of the own aircraft is predicted by utilizing a probability distribution. This approach ensures that all potential positions of the aircraft within the near future are considered while weighting the most likely flight path. A conflict detection algorithm initiates an alarm in case the threat probability exceeds a threshold. An escape manoeuvre is generated taking into account all potential hazards in the vicinity, not only the one which caused the alarm. The pilot gets a visual information about the type, the locating, and severeness o the threat. The algorithm was implemented and tested in a flight simulator environment. The current version comprises traffic, terrain and obstacle hazards avoidance functions. Its general formulation allows an easy integration of e.g. weather information or airspace restrictions.